PACIFIC AND BEERING’S STRAIT. 
2S7 
we made some experiments on the temperature of the sea at intermediate CH Ap. 
depths, as low as 760 fathoms, where it was found to be twenty-eight 
degrees colder than at the surface ; two days afterwards another series 
was obtained, by which it appeared that the temperature at 180 fa- 
thoms was as cold as that at 500 fathoms on the former occasion, and 
it was twenty degrees colder at 380 fathoms on this, than it was at 760 
fathoms on the other. Between these experiments we entered a thick 
fog, which continued until we were close off* the Kamschatka coast ; and 
We also experienced a change of current, both of which no doubt con- 
tributed towards the change of temperature of the sea, which was much 
greater than could have been produced by the alteration in the situation 
of the ship : the fog by obstructing the radiation of heat, and the cur- 
rent by bringing a colder medium from higher latitudes. About this 
period we began to see drift wood, some of which passed us almost daily. 
The sea was occasionally strewed with moluscous animals, principally 
heroes and nereis, among which on the 19 th were a great many small 
crabs of a curious species. Whether it was that these animals preferred 
the foggy weather, or that we more narrow'ly scrutinized the small space 
of water around us to which our view was limited, I cannot say, but it 
appeared to us that they were much more numerous w^hile the fog 
lasted than before. 
In the afternoon of the 23d, in latitude 44° N., the wind, which had 
been at S. W., drew round to the west, and brought a cold atmosphere 
in which the thermometer fell fourteen degrees ; it is remarkable that 
sixteen hours before this change occurred, the temperature of the sea 
fell six degrees, while that of the atmosphere was affected only four 
liours previous. In my remarks on our passage round Cape Horn, I have 
mentioned the frequency with which the temperature of the surface 
of the sea was affected before that of the atmosphere when material 
changes of wind were about to occur. 
On the 26th, in latitude 49° N., after having traversed nearly seven 
hundred miles in so thick a fog that we could scarcely see fifty yards 
from us, a north-east wind cleared the horizon for a few hours : this 
change again produced a sensible diminution of the temperature, which 
"as thirty-one degrees lower than it had been thirteen days previous. 
